As information technology advances, the amount of digital information to be stored has greatly increased, resulting in wide utilization of optical discs. However, the optical disc may be inadvertently damaged by scratches in utilization, which may cause loss of data.
Nowadays, the use of optical disc as information storage means has become commonplace and is diversified in different types such as video compact disc read-only-memory (CD-ROM), compact discs (VCD), or digital versatile discs (DVD). If the optical disc is scratched, different kinds of undesired effects may be produced when the optical disc is read, depending upon the types of digital information stored. If the optical disc stores audio data, undesired effects may be sound jumps. If the optical disc stores video data, scratch damages on the optical disc may result in image immobilization or mosaic effects. In the worse cases, the data pickup head may be incapable of accessing the data on the damaged optical disc that then becomes useless. Further, since the material used to fabricate the optical disc is usually not recyclable plastics, the increasing use of optical disc may represent a source of pollution in long term. An ecological solution to this problem would be repairing the damaged optical disc so that it can have a longer service life.
Presently, various types of disc cleaning apparatus may be found on the market, but most of them are only capable of cleaning function. Some commercially available products further may be advertised as being able to provide repairing function of the damaged optical disc, but they actually fill the scratches on the optical disc with wax material. A disadvantage of this solution is that if the liquid wax is not properly disposed, it may cause further scratch damages after solidification. Therefore, an effective solution to disc repairing is still subject to research and development in the present state of the art.
In the fabrication process of an optical disc, a disc substrate after having undergoing processing steps of dye coating then usually has to be provided with a metallic film thereon (usually gold, silver, or copper) to allow an adequate reflection of the laser beam with a proper intensity. The metallic film is typically formed and adhered on the dye recording layer via vacuum spraying or sputtering. A UV-cured resin then is used as protective layer.
U.S. Pat. No. 6,386,946, filed by the same inventor of the present application, discloses an optical disc repair machine suitable for performing cleaning, maintenance, and repair of an optical disc. In this known machine, the damaged disc to be repaired by grinding is put in place on a disc turntable. A grinding wheel is mounted on a grinding arm, and during grinding on the optical disc is supplied with a grinding agent. When the repair machine is turned on, the disc turntable is driven in rotation and the grinding wheel is applied against the optical disc to undergo grinding. The grinding wheel and agent may be of different types to satisfy different levels of grinding, e.g. coarse level, medium level, and fine level. The fine level particularly is dedicated to disc polishing. The damaged optical disc thereby can be progressively ground, polished and rectified until a desired flat surface without defect is obtained.
Although the above repair machine has convenient functions of grinding, polishing and rectifying the optical disc, the size of its structure however is large and its construction is relatively complex. Practical implementation of such a repair machine therefore remains problematic for the disc manufacturer, as well as the entertainment producing company or the music/movie renting shop. It is even less practical for the ordinary terminal consumer who demands for miniaturized, portable and convenient systems.